For example, as a package bag for food and drink, flavoring and others of liquid, jelly or the like having a volume of more than 100 ml, there is a bag formed by thermal-fusing a capped pouring nozzle made of an injection molded plastic onto an inner face of a relatively hard package bag main body including an aluminum foil. In this case, the packing material can be poured over plural times by the detaching and screwing operation of the cap with respect to the pouring nozzle.
In this package bag, however, the cost of the pouring nozzle and cap as a plastic shaped product becomes high, and there is the burden of the handling that the complete thermal fusion of the pouring nozzle having a three-dimensional stereo form onto the package bag main body under a sufficient joining strength is difficult even by using a special heat-seal means or the like but also it is required to conduct the detaching and rescrewing of the cap every the pouring of the packing material. Furthermore, as to the package bag being relatively hard and hardly causing the crush deformation, it is necessary to replace the packing material with ambient air in the package bag and also the invasion of ambient air into the interior of the package bag is unavoidable up to the screwing of the cap to the pouring nozzle after the completion of the pouring, so that there is a problem that the packing material is contaminated by dust, virus and the like in the ambient air, or the ambient air itself oxidizes the packing material to damage the taste or the like of the flavoring and alcohol drink.
The invention is the subject matter to solve the above problems of the conventional techniques. A first object of the invention is to provide a cheap liquid pouring nozzle having a self-seal one-way function adapting to a soft package bag main body based on shrink or collapse deformation when the pouring of a packing material from a package bag is carried out without entrapping air into the package bag and automatically closing the pouring port with the wetting of the packing material at the same time of stopping the pouring the packing material to surely prevent the invasion of air into the package bag, which can be produced simply without requiring the detaching operation of a cap to the pouring nozzle and can always conduct surely and easily the integral uniting with the package bag main body or the pose fusion joining thereto, as well as a package bag using the same.
As a box-shaped vessel used for pouring the liquid packing material filled therein plural times are generally and widely used various paper cartons such as milk package, fruit juice package and the like.
The paper carton is used as a package vessel for the packing material having a volume of, for example, about 100-3000 ml, and is easy in the handling as compared with a glass bottle, a plastic bottle, a can and the like, and has a merit that the floor area efficiency is higher than those of various bottles, cans and the like having an outer profile form of a circle in the display at stores.
However, this type of the paper carton itself is assembled by fusion-joining a resin material and the packing material is directly filled in an inside thereof, and further it is required to provide a sufficient resistance to wettability, so that a resin material such as polyethylene or the like is laminated at least onto both surfaces, and hence it is unavoidable to remove the resin material in the recycling of the paper carton. On the other hand, in the production of the paper carton itself, it is necessary to use 100% virgin pulp and there is a problem that waste paper can not be used.
Further, in the opening of the paper carton having a roof form in its top, there are problems that it is required to peel off the fusion-joined portion of the resin material in the roof-shaped top through fingers but also it is frequently impossible to conduct the adequate opening and further it is impossible to sufficiently close the opened portion.
On the contrary, the paper carton of a brick type having a flat top has still a trouble in the opening that the fused end portion folded toward the side wall is cut by scissors, but the opening as is expected is surely conducted by such a cutting and also it is possible to close the opened portion by folding the fusion-joined portion toward the side wall.
In the paper carton of the brick type, however, there is a problem that a fear of flowing down the packing material in an unintended direction is high in the first pouring because the filling height of the packing material becomes frequently close to the opening height.
It is, therefore, the second object of the invention to solve the above problems of the conventional paper cartons and to provide a box for a package bag wherein a packaging structural body is functionally separated into a soft package bag developing a filling and packaging function and a box for package bag giving a fixed formability thereto to omit a laminate of a resin material to the box body and make the use of waste paper possible and further the trouble of the opening in the box body is removed to simply and surely conduct the opening as is expected and also the closing of the opened portion is sufficiently ensured and further the flowing direction of the packing material is easily specified, as well as a packaging structural body using the same.